The first boss of Deepstrike Mines. Overseer Markus begins with a handful of non elite mobs. Upon pulling, have your DPS AoE them down. They should not be a big burden.

Overseer Markus' only ability is a cleave, so make sure your tank turns him away from the rest of your group.

At 50%, Overseer Markus will split into 3 elite adds and temporarily despawn. They are very simple and do not hit hard. As the tank, just be sure to pick them up quickly. Once all 3 are dead, Overseer Markus will return. Continue killing Overseer Markus at this point.

(2) Gregori Krezlav

The second boss of Deepstrike Mines. Gregori Krezlav is a pure caster. He will cast Rend Life, which is a single target direct-damage ability, on the tank.

There are two phases to the fight. Phase 1 is when Gregori Krezlav is active. Besides spamming Rend Life, he will summon a Baneful Delver, an elite add. This must be killed or crowd-controlled.

Phase 2 begins when Gregori Krezlav becomes immune and spawns 3 Risen Channelers. Although the Risen Channelers do nothing, Gregori Krezlav will continue casting Rend Life. He will not summon anymore adds during Phase 2. Phase 2 ends when all 3 Risen Channelers are dead.

The fight returns to Phase 1 and continues until Gregori Krezlav is dead.

(3) Bonehew the Thunderer

The third boss of Deepstrike Mines. Bonehew the Thunderer is much more difficult than the previous two bosses. However, if your group is able to get the mechanics of the fight down pat, the fight is simple.

Throughout the fight, Bonehew the Thunderer will hit people within melee range with AoE's that will stun for a couple of seconds. Therefore, your healer cannot be in mele range.

However, Bonehew the Thunderer's most important ability is the Seismac Smash. Very frequently, Bonehew the Thunderer will pick a random plank and run to its end. He will turn and face the same direction that the plank runs across the platform and use Seismac Smash, sending a powerful AoE knockback directly across the plank. Anyone within its range will take a lot of damage and get knocked back, possibly knocked off the platform.

The easiest method of avoiding Seismac Smash is to always stand at a 90 degree angle to Bonehew the Thunderer. When Bonehew the Thunderer selects a plank, continue standing 90 degrees to him. If you are standing 180 degrees (directly across the platform from him), you will get hit and most likely knocked off the platform (if you survived the hit). You can also stand directly on top of him as long as you are not standing in front of him. This works well for melee DPSers.

Bonehew the Thunderer will return to the tank after Seismac Smashing. The fight will just repeat itself from there. If your group can avoid being hit by Seismac Smash, it will be an easy victory.

(4) Gatekeeper Kaleida

The last boss of Deepstrike Mines. Gatekeeper Kaleida is by far the toughest boss of the instance. He has much more health than the previous bosses, hits much harder, and has a fight mechanic that requires your group to be on their toes at all times and do high DPS.

Gatekeeper Kaleida has two phases, a Fire Phase and Earth Phase. You can tell which phase he is in by his buff. He will either have a red Fire Buff or green Earth Buff.

Fire Phase
This is the DPS phase. During this phase,
Gatekeeper Kaleida summons Fire Crystals. A Fire Crystal will be 'thrown' at a random party member. When it lands, it will cause damage and knockback those close to it. It will then pulse AoE Fire damage for about 15 seconds. At that point, it will explode, causing a lot of damage to anyone within 15-20 meters of it.

In addition, Gatekeeper Kaleida will be casting a Cleave and melee-ranged AoE. The AoE is called Fireblast. Your melee can avoid being hit by this if they run out of range while it is being casted. This can save your healers a lot of mana.

Earth Phase
This is the important phase. During this phase, Gatekeeper Kaleida summons Earth Crystals. An Earth Crystal will be 'thrown' at a random party member. When it lands, it will cause damage and knockback those close to it. It will then begin healing Gatekeeper Kaleida. Your group must destroy Earth Crystals as fast as possible. The longer an Earth Crystal is up, the more Gatekeeper Kaleida will heal - making this fight take a very long time!

In addition, Gatekeeper Kaleida will be casting a melee-ranged stun. It is an instant cast stun and cannot really be avoided other than standing outside melee range.

Strategy
Keep in mind that each phase will summon 2 crystals. Afterwards, Gatekeeper Kaleida will switch to the other phase. In order to successfully defeat Gatekeeper Kaleida, you must do the following:

-Avoid Fire Crystals. Do not stand near them when they pulse or explode.
-Quickly destroy Earth Crystals. Do not let them heal Gatekeeper Kaleida more than a few percent each time.
-Do not get hit by Gatekeeper Kaleida's many short-ranged AoE abilities. If you are a melee, avoid Fireblast.

This fight is very healing intensive. Your healer must do everything necessary to not run out of mana. It is very suggested to have a Cleric and a support healer. Your 2 DPS roles must be pure DPS'ers, otherwise the Earth Crystals will heal for too much.

Overall, this is a very difficult fight that requires a strong tank, a great healer, and high DPS.